Ross this is not disabling HDMI. This is disabling the high definition controller completely. Disabling this will turn the onboard sound off.
Wouldn't disabling HDMI support for video cards be located within the Video settings?
LOL....if you look at my screenshot you'll see that under sound devices I have a sound blaster audigy and an HDMI. The HDMI actually belongs to the graphic card...Weird I know but higher end ATI graphic cards do have a HDMI controler. It's also been discovered that if you don't actually use it then turning it off will give you more performance. This is true. I guess more of the cards power is given over to the graphic side of things.
Now in ante's case i got confused somewhere his and Ians post, so thought that he had a card like mine.. After rereading i then told him to turn it back on...So sorry for any confusion caused...
Edit: I found one article that deals with this but not the original one i read but the ideas the same...I'll paste part of it here:
Radeon HD 2000 series fixed the HDCP issue and things went back to normal, but now
Hardware-Infos claim that you actually lose a little bit of 3D performance if you drive the audio through the graphics card. While in theory this should not happen - as HD audio is just passing through the PCI express bus and being synced with the picture, independent testing is now showing that Radeon 4800 series suffers from a small performance drop regardless of HDMI being an active connection or not.
Benjamin discovered that disabling the "ATI Function Driver for High Definition Audio" in Device Manager brings a small performance boost.
In games such as Crysis Warhead, Far Cry 2, GRAW 2, GTA IV, Tom Clancy HAWX and Stalker: Clear Sky in 1920x1200, with 4x AntiAliasing and 16x Anisotropic Filtering, disabling the "ATI Function Driver for High Definition Audio" brought anywhere between two and five percent. Most of applications saw a difference between 2-3 percent [inside the margin of error], but five percent is a tangible difference.
Taken from here:
http://www.brightsideofnews.com/new...io-driver-reduces-radeons-3d-performance.aspx
@ Ante
So from what your saying, you only have the online version of Halo? Hmm... it'll still need updating if possible. Also if you list your machine spec I'll point you in the right direction for drivers.. It's usually always best to keep
All drivers up to date. This includes motherboard/chipset, sound and graphics as well as anything else thats needed..